Fastigilin C and radiatin are anti-neoplastic pseudoguaianolides obtainable in very minute quantities from natural sources. Synthetic routes to these compounds have evaluated and one promising stereocontrolled, multi-step sequence to the racemic natural products is well underway. A second, totally different strategy will employ enantioselective stages so that fastigilin C and other bioactive cogeners can be prepared in optically-active form. This research will provide access for the first time to pseudoguaianolides functionalized at both C-6 and C-9.